In today's wide network enterprise, security has become a major concern to prevent unauthorized access to the many computer systems of the network. Computer systems within one business site are typically connected using a Local Area Network (LAN) and a Network Administrator is responsible for keeping the network up and running properly. As local area networks (LANs) continue to proliferate, and the number of personal computers (PCs) connected to LANs continue to grow at a rapid pace, network security becomes an ever increasing problem for network administrators.
As the trend of deploying distributed LANs continues, this provides multiple access points to an enterprise network. Each of these distributed access points, if not controlled, is a potential security risk to the network. Among these risks, the virus attacks impact strongly all IT infrastructures by the very fast spreading of the virus. A specific kind of virus which represents more than ⅓ of the total attacks is the well-known ‘Worm’ virus. This latter makes use of security loopholes in operating systems and spread from one system to another via networks through well-known TCP/IP port numbers 137,139 and 445.
TCP/IP is the acronym of Transmission Control Protocol/Internet Protocol (TCP/IP) ports numbers 137 (namely the Net BIOS Name Service), 139 (namely the Net BIOS Session Service) and 445 (namely the Microsoft-DS).
Another risk is the voluntary attack and the unauthorized access to protected resources (using also the spoofing).
A common misunderstanding is that firewalls recognize attacks and block them. Firewalls are simply a device that shuts off everything, and then turns back on only a few well-chosen items. In a perfect world, systems would already be “locked down” and secure and firewalls would be unneeded. The reason of having firewalls is precisely because security holes are left open accidentally.
Thus, when installing a firewall, the first thing it does is stopping all communications. Then the firewall administrator carefully adds “rules” allowing specific types of traffic to go through the firewall. For example, a typical corporate firewall allowing access to the Internet would stop all User Datagram Protocol (UDP) and Internet Control Message Protocol (ICMP) datagram traffic, stops incoming TCP connections but allows outgoing TCP connections. This stops all incoming connections from Internet hackers but still allows internal users to connect to the outgoing direction.
A firewall is simply a fence around the network with a couple of well chosen gates. A fence has no capability of detecting somebody trying to break in (such as digging a hole underneath it), nor does a fence know if somebody coming through the gate is allowed in. It simply restricts access to the designated points.
Finally, a firewall is not a dynamic defensive system. In contrast, an intrusion detection system (IDS) is much more of that dynamic system. An IDS does recognize attacks against the network that firewalls are unable to see.
Another problem with firewalls is that they are only at the boundary of the enterprise network. Roughly 80% of all financial losses due to hacking come from inside the network. A firewall at the perimeter of the network sees nothing going on inside; it sees only that traffic passes between the internal network and the Internet.
Log files and other accounting mechanisms can be used to track users and their activities. Using log files and audit information is known as passive detection since they rely on a passive analysis set of data. The system administrators are responsible for reviewing the operating system security event logs to determine if a system attack or breach of security has occurred. Some known products allow to review those logs such as Tivoli Risk Manager from the Assignee and GFi LANguard S.E.L.M. from GFI Software Ltd.
Tivoli Risk Manager is based on a framework infrastructure allowing a cross operating systems availability (OS/2 (OS/2 is a Trademark of IBM Corporation), Windows (Windows is a Trademark of Microsoft Corporation), Linux (Linux is a Trademark of Linus Torvalds) and AIX (AIX is a Trademark of IBM Corporation)) to report the alerts on a centralized console. This solution offers the possibility for the administrator to create the appropriate relationships between various security alerts. However, the relationships concerning the Net BIOS invalid attempts between different operating systems are not deeply analyzed and do not relate to external databases.
GFi LANguard S.E.L.M. is a security event log monitor that collects all security events in one central database, create reports and custom filters. This solution suffers from the limitation of operating on one Operating System only, namely Windows, thereby leaving attacks possible for others operating systems.
More generally, all existing solutions leave the administrators with receiving a large number of false warning messages that compel to spend a lot of time analyzing manually those messages and sorting out the non relevant violations from the true ones.
Therefore, there is a need for a solution that overcomes the aforementioned drawbacks.
However, the drawback of this solution is that all the source information is coming from built-in log files from Operating Systems, and those log files give only the workstation/computer name of the attacker device. If this computer name is not registered in any Domain Name Server (DNS) servers, or is unknown from the victim company, it is often impossible to locate physically this attacker device.
With those existing analyzing solutions, the problem remains because as the log alert is done after the security event, there is no way to check if a device is connected on a victim server, as there is no built-in way to check the history of TCP/IP ports into one Windows server.
Others TCP/IP logger tools exist but require a manual check of the log files after the security event occurs to find if there were remote attacks.
Moreover those TCP/IP tools require to look deeply into the TCP/IP stack (the software that looks the TCP/IP protocol) and are not able to verify if one Windows Logon 137/139/445 is normal or not, if it happens into a Windows file server that has as primary role to give access to the 137/139/445 TCP ports.
So, this is the main drawback of those log analysis methods. Moreover it takes time to analyze and physically locate the attacker device and to disconnect it.
The present invention offers a solution to remove those drawbacks.